The present invention relates to a gas-liquid separator.
When bubbles are entrained in industrial water such as boiler water, working liquids (including non-flammable ones) used in hydraulic systems, slurries used in the production of ceramic, slurry-like coating agents used for coating paper, films or tapes, lubricating oils, quenching liquids, chemical solutions, edible liquids, etc., equipment, apparatus or devices handling these liquids are damaged, poor yields result and non-uniform structures occur. In addition, aeration and cavitation cause erosion, noise and degradation of fluids. Therefore bubbles entrained in liquids must be removed.
The prior art gas liquid separators or more specifically bubble separators are shown in FIGS. 1 and 2. With the static tank shown in FIG. 1, liquid entraining bubbles enter through an inlet a into the tank b which is provided with baffles c to define zig-zag channels. While the liquid flows through these channels, bubbles in the liquid are separated by the action of the buoyant force on the bubbles and collected. The liquid free from bubbles flows out through an outlet d. Instead of the baffles, wire mesh or the like may be used.
In the continuous-flow type bubble separator shown in FIG. 2, an inner pipe f extended coaxially of an outer pipe e is bent upright and extended out of the outer pipe e. The bottom of the inner pipe f is provided with many openings g so as to direct the liquid which enters the inner pipe f through an inlet h into the outer pipe e. While the liquid flows through the inner pipe f, bubbles in the liquid are separated and rise by the action of the buoyant force on the bubbles and are discharged through a valve i to the exterior. The liquid free from bubbles flows out through an outlet j.
In the bubble separators shown in FIGS. 1 and 2 bubble or entrainment separation relies on the action of the buoyant force on the bubbles. As a result, in the case of a liquid having a high degree of viscosity, the bubble-liquid separation efficiency is low. In addition, because of the slow rise time of the bubbles, the separators become very large in size.
In order to solve these problems, a bubble separator of the type shown in FIG. 3 has been devised and demonstrated. Disposed at the bottom of a cylindrical chamber k of the bubble separator is an agitator m which has a plurality of fins 1 and is carried for rotation by a shaft n drivingly connected to a motor or the like. A liquid with entrained bubbles is charged through an inlet o opening at the upper portion of the cylindrical chamber k. In the chamber k the liquid is subjected to a flow pattern forming a vortex. As a result, the bubbles in the vortex are forced to rise toward a trap or bubble outlet q and are discharged through a valve r to the exterior. The liquid free from bubbles flows out through an outlet p.
The bubble separator shown in FIG. 3 has a higher bubble separation efficiency than those shown in FIGS. 1 and 2, but has some disadvantages. Firstly, if abrasive particles are entrained in a liquid, a seal s between the rotary shaft n and the bottom of the chamber k is subjected to rapid wear and must be frequently replaced. Secondly, the construction is complex so that the fabrication cost becomes high for general usage. Thirdly, the power for driving the agitator must be provided.
In view of the above, the primary object of the present invention is to provide a gas-liquid or bubble separator which will prevent erosion, noise, degradation of fluids, damage of equipment and poor yields, will positively separate bubbles entrained in a liquid having a high degree of viscosity and will ensure trouble-free operation even when abrasive particles are also entrained in the liquid.
Another object of the present invention is to provide a gas-liquid or bubble separator which is very simple in construction yet capable of positive separation of bubbles from a liquid.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawings.